Inverter Compressor Drive Error Diagnosis And Solution - Pioneer CB009GMFILCFHD Service Manual

16.3.10 Inverter compressor drive error diagnosis and solution(P4)
Error Code
Malfunction decision
conditions
Supposed causes
Trouble shooting:
P4
An abnormal inverter compressor drive is detected by a special
detection circuit, including communication signal detection,
voltage detection, compressor rotation speed signal detection
and so on.
Wiring mistake; IPM malfunction; Outdoor fan ass'y faulty
Compressor malfunction; Outdoor PCB faulty
101